1. Field of the Invention
This invention relates to the field of solar energy, and more specifically to systems for collecting, concentrating and converting solar energy to a more readily distributed form of energy.
2. Related Art
Efficient collection of solar energy entails capturing as much of the incident sunlight striking a given site space, ensuring a minimum amount of land is consumed for energy generation purposes. The high cost of conventional solar collectors and their intolerance to being shadowed has led tracking solar power plant designers to typically distribute solar collectors with a site utilization collection efficiency of less than 50 percent. Two axis-tracking photovoltaic systems typically deliver more energy per solar collector than fixed photovoltaic systems but require more land, with less than 25 percent site utilization collection efficiency being typical.
Concentration of the sun's rays can significantly reduce the amount of energy conversion material required to create a given amount of power. Using concentration lenses reduces the expensive energy conversion device's size and relative cost. When solar concentration is utilized, tracking the sun's position in the sky is typically required to deliver the sun's concentrated energy accurately to a smaller target. Single axis tracking systems are known in which the sun is tracked only around the azimuth axis, but in such systems a positional variation of the focal point with various sun heights typically causes significant inefficiencies in solar concentration. On the other hand, the electromechanical systems required to accurately track the sun's position and hold the collector in position for two-axis tracking systems have historically consumed gains that might be realized by using concentrated sunlight and smaller energy conversion devices. Thus, there is a need for cost-effective solutions to tracking and concentrating sunlight onto relatively small conversion devices.
Converting concentrated sunlight into electricity typically results in substantial waste heat. Therefore, there is need for an efficient thermal management process that provides a reliable method of removing such waste heat from the energy conversion device. Most approaches to solving this problem require an active pumping process and distribution system that involves water moving though tubes and hoses, requiring the system to be failure-free in order to ensure survival of the energy conversion device in the harsh concentrated sunlight. A single failure of the cooling system is likely to irreparably damage the costly energy conversion devices.